ISS Robot Arm Malfunctioning: NASA Plans Spacewalk Repair for June 30
The International Space Station’s critical Canadarm2 robotic arm has been offline since late May due to a mechanical malfunction, with NASA and the Canadian Space Agency planning a spacewalk on June 30 to replace a faulty wrist joint.
Canadarm2, built by MDA Space for the Canadian Space Agency and now in its 26th year of service, exhibited abnormal behavior during routine operations on May 27, 2026. “The system demonstrated an elevated motor current in a wrist joint, and arm motion did not occur as expected,” NASA said in an official statement. The arm was moved to a safe, stable configuration immediately after the anomaly was detected.
### Impact on Station Operations
With Canadarm2 out of commission, standard cargo spacecraft berthing operations are affected. The 17.6-meter (58-foot) robotic arm is the primary tool for capturing and berthing Cygnus and Dragon cargo spacecraft carrying food, equipment, and supplies to the crew. It also performs a significant share of external station maintenance tasks.
The Japanese robotic arm on the Kibo module remains operational and has been used this week for CubeSat deployments, but it cannot fully substitute for Canadarm2’s reach and capability across the station’s US orbital segment.
No crew members were in danger during the incident. The arm was safely parked, and the station continues to operate normally in all other respects.
### The Repair Plan
Canadarm2 was designed from the start for orbital servicing. Its modular segments can be unbolted and replaced in space, a feature that has proven essential over its long service life. A similar wrist roll joint replacement was performed in 2002, and a latching end effector (one of the arm’s “hands”) was replaced during a spacewalk in 2017.
A spare wrist joint is already aboard the ISS, pre-positioned by the Canadian Space Agency as part of its long-term spares strategy. The repair will require a spacewalk (EVA) scheduled for Tuesday, June 30, 2026. CSA officials have described the procedure as comparable to “changing the tire on a car” in terms of complexity, though the space environment adds significant operational constraints.
The spacewalkers are expected to come from the Expedition 74 US-side crew: NASA astronauts Chris Williams, Jessica Meir, and Jack Hathaway, or ESA astronaut Sophie Adenot. NASA plans to announce the specific crew assignment at a future news conference.
### Historical Context
Canadarm2 passed its 25th anniversary of continuous operation in space in April 2026. It was launched aboard Space Shuttle Endeavour in April 2001 and has since been used for hundreds of tasks: capturing cargo spacecraft, performing station assembly, supporting spacewalks, and inspecting the station’s exterior.
The arm’s longevity is a testament to its modular, repairable design. Unlike most spacecraft systems, Canadarm2 was built to be serviced in orbit, with replaceable joints, end effectors, and electronics. This maintainability has allowed it to far exceed its original 15-year design life.
With the repair spacewalk set for June 30 one day before Canada Day the arm is expected to return to full service shortly afterward, ending a roughly five-week operational pause.